1. Field of the Invention
This invention relates to a vehicle control system and more particularly to a vehicle control system which opens the way to the incorporation in the control of such non-physical factors as human judgments and impressions.
2. Description of the Prior Art
Vehicle devices and mechanisms that formerly were operated manually by the vehicle driver are, more and more, being controlled automatically. An example of such automation can be seen for instance, in the technology described in Japanese Patent Publication No. 59(1984)-9740, which discloses an autocruise control system.
Such conventional automatic control has employed various techniques including proportional control, proportional-plus-integral control and proportional-plus-integral-plus-differential control. In all cases, however, the control techniques have been premised on receiving physical quantities as input values. The physical quantities are represented numerically and input to the control system as parameters indicating states of vehicle operation, whereafter control values are computed in accordance with an appropriate manner. In this kind of control, however, it is impossible to include among the control factors things that are difficult to express clearly as physical quantities, such as the feelings and judgments of a human being. Thus the conventional control systems are unable to incorporate into the automatic control the manual driving techniques which a skilled driver uses on a non-automated vehicle to realize safety and economy as well as riding comfort and enjoyment. One of the reasons for this is that, as stated above, the feelings, judgments, impressions and the like of the skilled driver cannot be expressed as physical quantities and thus cannot be used as control factors in the systems. Such a skilled driver operates an accelerator pedal and a shift lever or the like during driving of his vehicle while making judgments with regard to the constantly changing surrounding circumstances, and in the process of doing this makes predictions regarding circumstances apt to arise in the future. With the conventional control systems, however, there is no hope of being able to incorporate such predictive judgments into the automatic control.
For the same reason, the conventional control techniques are unable to respond to the difference or diversity in feelings among individual drivers. As a result, it has not been possible to adequately give each individual driver a feeling of oneness with the vehicle, i.e. to give him the feeling that the vehicle is an extension of himself. Moreover, in the conventional control system, the control technique have become increasingly complicated and detailed year after year. Thus, when a microcomputer is used in the system, it is disadvantageously necessary to employ a memory of large capacity.